The present invention relates to a battery charging control system, and more particularly relates to a battery charging control system which automatically monitors the temperature, voltage, and power level of a battery set so as to charge the battery set automatically and properly according to the conditions monitored without causing any damage to the battery set.
Mobile telephones have become more and more popular because of the advantage of mobility. Various types of rechargeable batteries including nickel-cadmium, nickel-hydrogen, and lithium batteries have been disclosed for use in mobile telephones. These mobile telephone battery have drawbacks as follows:
1) Limited battery capacity limits the working time of the mobile telephone. If one tries to increase the capacity of the battery, one must increase, relatively, the size of the battery. This will thereby affect the mobility of the mobile telephone. PA1 2) Simply increasing the capacity of the battery cannot provide the mobile telephone with unlimited power supply, and therefore spare batteries must be available. PA1 3) It is inconvenient to charge the battery of a mobile telephone, and it is also difficult to obtain an external power supply for charging the battery. PA1 4) It takes a long time to fully charge the battery of a mobile telephone (normally about 10 hours). The use of a rapid battery charging charger may produce high temperatures, causing the battery to be damaged. PA1 5) It consumes energy when an external power supply is employed to charge the battery of a mobile telephone. PA1 6) According to conventional battery charging methods, there exists the problem of a battery's "memory effect", which cause the capacity of the battery reduced or even causes the battery to be damaged. The battery's "memory effect" happens when the battery is charged before its power supply is completely used up or when an electric leakage has occurred. Because the voltage of the battery drops when it is at a low power state or when an electric leakage happens, the residual volume of power of the battery will be memorized when it is charged with an external power supply of a higher voltage. This residual volume of power will occupy the capacity of the battery causing the available capacity of the battery to be reduced. The accumulation of such residual volumes of power will finally cause the battery to become unchargeable. When the battery becomes unchargeable, the user must replace the battery of the mobile telephone with a new battery. PA1 7) Conventional batteries cannot be charged with full load current or high voltage when the temperature of the batteries is below 5.degree. C. or over 50.degree. C. When the temperature of a conventional battery is below 5.degree. C. or over 50.degree. C., it will be damaged when charged with a full load current or a high voltage. PA1 1) It has a high voltage regulation and control protection to maintain the battery voltage within 12V.+-.4V, the battery current at 1A, and the volume of battery power within a normal level. PA1 2) It automatically regulates the voltage and current of charging power supply when the temperature of the battery increases during the rapid charging mode. PA1 4) It automatically monitors the conditions of the battery so as to automatically regulate the charging power supply to charge the battery according to its conditions. Therefore, the battery charging control system is practical and safe in use. Under the rapid mode, a battery can be charged to the saturated status within about one hour. PA1 5) Because the battery charging control system monitors the battery to be charged and then charges it automatically according to the conditions of the battery monitored, the battery charging control system is suitable for charging any of a variety of conventional-rechargeable batteries. PA1 6) Any light source can be used for charging batteries, and batteries can be charged while they are being used. PA1 7) The light energy collector panel can be made according to the desired shape and size to effectively collect the light energy for charging the batteries rapidly. PA1 8) It automatically cuts off the circuit when the controlled battery set is at the saturated status. PA1 9) It eliminates the problem of "memory effect"; and therefore the service life of the controlled battery set is prolonged. PA1 10) The controlled battery set, can be charged either with light energy or an external power supply.